Hopper or tank trailers are commonly used to transport dry bulk such as industrial and food products. The trailer has a plurality of funnel shaped hoppers located at the bottom of the trailer. Defined at the lower most end of each hopper is a discharge outlet. Attached to each discharge outlet is a valve member and a hopper tee. The hopper tee has a vertical section and a horizontal section forming the tee configuration. The valve member is located between the discharge end of the hopper and the top of the hopper tee. A plurality of connection pipes are connected the horizontal sections of the hopper tees to allow the dry bulk to be discharged from a single discharge opening.
When the hopper trailer reaches its destination, the dry bulk is unloaded. The unloading process involves attaching a discharge pipe to the discharge opening of the trailer. The valve members are then positioned to the opened position such that the dry bulk is able to flow freely into the hopper tees. Thereafter, a reduced pressure in the discharge pipe suctions the dry bulk through the bottom lines and into the discharge pipe.
Although the prior art hopper tee assemblies function well for their intended purposes, there are several problems associated with the prior art valve member and hopper tee assemblies. The prior art valve member and the hopper tee assemblies are bolted to a flange located at the bottom of the hopper. To gain access to the valve member or the interior of the hopper tee, a wrench must be used to unbolt the bolts that hold the hopper tee and the valve member to the flange. The process of unbolting the bolts is very time consuming.
U.S. Pat. No. 5,842,681 to Sisk addresses the concern of having to remove the bolts to gain access to the valve member or the interior of the hopper tee, by replacing the conventional flange, the valve member and the hopper tee with a swing-away hopper tee assembly. While the '681 Sisk hopper assembly can be easily opened without the necessity of unbolting, the '681 Sisk hopper assembly is significantly taller than the conventional valve member and hopper tee which it replaces. Therefore, to retrofit a trailer with the '681 Sisk hopper assembly, the bottom of each hopper would need to be reduced to accommodate for the increased height of the Sisk hopper assembly. Such a retrofitting process is very time consuming and costly.
As discussed previously, a plurality of connection pipes are connected the horizontal sections of the hopper tees. A vacuum is sometimes employed through the connection pipes to facilitate the emptying of the dry bulk material. All of the dry bulk product must be removed at the end of unloading process to prevent contamination of subsequent loads. It is known that contamination can occur at the point of coupling of the connection pipe and the hopper tee. Hence, it may sometimes be necessary to remove the clamp assembly connecting the hopper tee to the corresponding connection pipe and unseat the gasket to gain access to the junction between the hopper tee and the connection pipe. It is known in the prior art to use a clamp assembly having semi-circular arms connected by a hinge. A lever and a clamping means is used to draw the two arms tightly together to surround a gasket situated radially outwardly of the junction between the hopper tee and corresponding connection pipe. U.S. Pat. No. 5,722,666 discloses such a clamp assembly. While the clamp assembly disclosed in the '666 Patent allows for quick removal of the clamp assembly; to gain access to the junction between the hopper tee and the corresponding connection pipe, a further step is still required to unseat the gasket by sliding the gasket along the hopper tee or the connection pipe.
Therefore, there exists a need for a clamp assembly which allows for easy access to the junction between the hopper tee and the corresponding connection pipe.